Chimpanzees love to share food, according to a new study published by The Proceedings of the Royal Society. Researchers found heightened levels of oxytocin in the urine of primates, leading to the conclusion that familial bonds are strengthened during mealtimes.
Both the giver and receiver of food have similar increases in oxytocin levels, showing that sharing food is mutually beneficial. The belief that giving is better than receiving is refuted by this study, because both actions yield the same level of oxytocin. Scientists from Europe and the U.S. studied dozens of wild chimpanzees in Uganda, and observed this sharing and giving behavior. Sharing food is more beneficial than mutual grooming, which is seen as a way of maintaining social relationships.
Roman Wittig from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and his colleagues collected 79 urine samples from 29 chimpanzees within an hour of the primates sharing and eating food in a social setting. The samples showed increased levels of oxytocin in all chimpanzees. It did not seem to matter whether the chimpanzees were related to each other, what kind of food was shared, or whether they were giving or receiving food.
Oxytocin levels in humans are increased when a mother nurses her infant. This can be considered the sharing of food, and thus forms a strong bond and increases oxytocin. This behavior is similar to the forging of social bonds between the chimpanzees when they share food, and can be a good predictor of cooperative relationships that can last months and even years. This is evidence that chimpanzees love to share food.
How chimpanzees came to be known so well by humans
The chimpanzee is the human’s closest relative. Both share similar DNA; in fact, only one percent of DNA is different. Intelligence, reasoning skills and emotions are only a few things chimpanzees and humans have in common.
Jane Goodall was 26 years old when she ventured to East Africa to achieve her childhood dream of studying chimpanzees. Dr. Louis Leakey, famed anthropologist and palaeontologist, was her mentor and he sent her into Tanganyika (now known as the Gombe Stream Reserve) in 1960 to study the wild chimpanzees. She was the first woman to do so.
What Goodall learned during those years of studying the chimpanzees was illuminating and yielded mounds of research on how similar chimpanzees are to humans. It didn’t take long before she observed their distinct personalities, emotions, ability to fashion different tools, and their reasoning and problem solving abilities. But it did take her many months to become familiar to the wild chimpanzees because they had no idea what sort of creature she was, and they would flee away in fright. Eventually, an adult male came close enough to Goodall that she named him David Greybeard. Goodall and her institute have followed David Greybeard’s family for the past 50 years. Scientists criticized her for giving the chimpanzees names.
As much as the chimpanzee and human have in common, there is a major difference: chimpanzees cannot speak. They do, however, have the ability communicate, notably with hand gestures and American Sign Language, which can be taught to them by humans. And, of course, chimpanzees love to share food, just as humans do.
By Juana Poareo